OBJECTIVE: To assess the effect of maternal cells or cellular components on neonatal immune responses to intracellular pathogens in calves. ANIMALS: 15 Holstein calves. PROCEDURES: Calves were fed whole colostrum, frozen colostrum, or cell-free colostrum within 4 hours after birth. Leukocytes were obtained from calves before feeding colostrum and 1, 2, 7, 14, 21, and 28 days after ingestion. Proliferative responses against bovine viral diarrhea virus (BVDV) and mycobacterial purified protein derivatives were evaluated. Dams received a vaccine containing inactivated BVDV, but were not vaccinated against mycobacterial antigens. RESULTS: All calves had essentially no IgG in circulation at birth, but comparable and substantial concentrations by day 1. Calves that received whole colostrum had enhanced responses to BVDV antigen 1 and 2 days after ingestion of colostrum. In contrast, calves that received frozen colostrum or cell-free colostrum did not respond to BVDV. No differences were identified among the 3 groups in response to mycobacterial antigens. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that transfer of live maternal cells from colostrum to neonatal calves enhanced responses to antigens against which the dams had previously responded (BVDV), but not to antigens to which the dams were na?ve (mycobacterial purified protein derivatives). Results suggested that cell-mediated immune transfer to neonates can be enhanced by maternal vaccination. 相似文献
The objective was to optimize rebreeding of nonpregnant, previously inseminated beef cattle. In Experiment 1, 43 cows received a used intravaginal progesterone-releasing insert (IVPRI; Days 0-7) 12.3 d after ovulation and received concurrently no treatment, 100 microg gonadotropin releasing hormone (GnRH), 1 mg estradiol cypionate (ECP), or 150 mg progesterone. Emergence of a new ovarian follicular wave was most synchronous (P < 0.0001) in the GnRH group. In Experiment 2, 675 heifers were given GnRH or no treatment on Day 0, fed melengestrol acetate (MGA; 0.5 mg/head/d) from Days 0-5 (Day 0 = 13-14 d after timed insemination; TAI), given 0.5 mg ECP or nothing on Day 7, and reinseminated 6-12 h after onset of estrus. Estrus was more synchronous (P < 0.05) in heifers given GnRH versus no treatment on Day 0. In Experiment 3, 317 TAI heifers were resynchronized with either MGA or a used IVPRI with or without ECP on Day 7; estrus was more synchronous (P < 0.05) and pregnancy rates were higher (54.1% versus 39.2%, P < 0.05) in heifers given a used IVPRI than those fed MGA. For resynchronization of heifers, pregnancy rates were not significantly improved with GnRH treatment, but were higher with a used IVPRI than with MGA. 相似文献
Canine osteosarcoma is an aggressive cancer, comprising 85% of canine bone neoplasms. Current treatment practices of surgery and chemotherapy increase 1-year survival by only 45%. The curcumin analogue RL71, has demonstrated potent in vitro and in vivo efficacy in several models of human breast cancer through increased apoptosis and cell cycle arrest. Thus, the present study aimed to investigate efficacy of curcumin analogues in two canine osteosarcoma cell lines. Osteosarcoma cell viability was assessed using the sulforhodamine B assay and mechanisms of action were determined by analysing the levels of cell cycle and apoptotic regulatory proteins via Western blotting. Further evidence was obtained using flow cytometry to detect cell cycle distribution and the number of apoptotic cells. RL71 was the most potent curcumin analogue with EC50 values of 0.64 ± 0.04 and 0.38 ± 0.009 μM (n = 3) in D-17 (commercial) and Gracie canine osteosarcoma cells, respectively. RL71 significantly increased the ratio of cleaved-caspase 3 to pro-caspase 3 and the level of apoptotic cells at the 2× and 5× EC50 concentration (p < 0.001, n = 3). Furthermore, at the same concentration, RL71 significantly increased the number of cells in the G2/M phase. In conclusion, RL71 has potent cytotoxic activity in canine osteosarcoma cells triggering G2/M arrest and apoptosis at concentrations achievable in vivo. Future research should further investigate molecular mechanisms for these changes in other canine osteosarcoma cell lines prior to in vivo investigation. 相似文献
The paper argues that conventional irrigation design processes rely heavily on predetermined design criteria, often without allowing for interactions with farmers and revising of criteria during implementation. Six cases from a tertiary development project in North Sulawesi, Indonesia are described, where farmers altered what had been designed and constructed by contracting and agency engineers. Through field inspections and farmer interviews, the farmers' alternative set of design criteria was elicited to explain why the farmers changed what had been constructed. A total of 27 cases are analyzed to show the relative importance of:
farmer criteria which are compatible with project criteria but which draw on local knowledge of the environment,
farmer criteria which were additional to project criteria and
farmer criteria which were incompatible with project criteria.
Some mechanisms are suggested for how to incorporate into the design process local knowledge, interactive learning and flexibility.
Human appropriation of net primary productivity (HANPP) is employed as a measure of human pressures on biodiversity, though largely at global and national scales rather than landscape to regional scales where many conservation decisions take place. Though gaining in familiarity, HANPP is not widely utilized by conservation professionals.
Objectives
This study, encompassing the US side of the Great Lakes basin, examines how regional distributions of HANPP relate to landscape-based biodiversity proxy metrics used by conservation professionals. Our objectives were (1) to quantify the HANPP of managed lands at the county scale; and (2) to assess spatial patterns of HANPP in comparison to landscape diversity and local habitat connectedness to determine if the metric can provide useful information to conservation professionals.
Methods
We aggregated forest and cropland NPP data between 2005 and 2015 and coupled it with previously published potential vegetation maps to quantify the HANPP of each county in the study region. We mapped the outputs at 500 m resolution to analyze spatial relationships between HANPP and landscape metrics of biodiversity potential.
Results
Area-weighted HANPP across our study region averaged 45% of NPP, down to 4.9% in forest-dominated counties. Greater HANPP correlated with reduced landscape diversity (p?<?0.001, r2?=?0.28) and reduced local habitat connectedness (p?<?0.001, r2?=?0.36).
Conclusion
HANPP could be used as an additional tool for conservation professionals during regional-scale land use planning or conservation decision-making, particularly in mixed-use landscapes that both support important biodiversity and have high levels of primary production harvest.
Three practical-type diets utilizing fishmeal and casein as the protein sources and containing fish oil (FO), safflower oil
(SO) or linseed oil (LO) were fed to duplicate groups of juvenile turbot (Scophthalmus maximus) of initial weight 1.2 g for a period of 12 weeks. No differences in final weight, mortality or development of pathological
lesions were evident either between duplicate tanks or between dietary treatments over this period. Fish fed diets containing
SO and LO contained significantly greater amounts of liver triacylglycerol compared to fish fed FO. The major C18 polyunsaturated fatty acids (PUFA) in SO and LO diets, 18:2(n-6) and 18:3(n-3) respectively, were readily incorporated into
both total lipid and individual phospholipids of turbot tissues. There was no accumulation of the Δ6-desaturation products
of these fatty acids, namely 18:3(n-6) and 18:4(n-3), in any of the tissues examined. The products of elongation of 18:2(n-6)
and and 18:3(n-3), 20:2(n-6) and 20:3(n-3) respectively, accumulated in both total lipid and phospholipids with the highest
levels of 20:2(n-6) in liver PC and 20:3(n-3) in liver PE. Eicosapentaenoic acid [EPA, 20:5(n-3)] levels exceeded those of
arachidonic acid [AA, 20:4(n-6)] in phosphatidylinositol (PI) from liver and gill of fish fed LO. EPA levels in liver PI from
fish fed LO were 3-fold and 2-fold greater than SO-fed and FO-fed fish, respectively. Fish fed diets containing SO and LO
had significantly reduced levels of AA in liver and muscle total lipid and lower AA in individual phospholipid classes of
liver and gill compared to FO-fed fish. The concentration of thromboxane B2 was significantly reduced in plasma and isolated gill cells stimulated with calcium ionophore A23187 of fish fed SO and LO
compared to those fed FO. Prostaglandin E produced by isolated gill cells stimulated with A23187 was significantly reduced
in fish fed both SO and LO compared to fish fed FO. 相似文献
The direct effects of osmotic pressure (salinity) on growth performance and lipid composition were investigated in fish cells
in culture. Cell lines from a relatively stenohaline marine species, turbot (Scophthalmus maximus) (TF) and an anadromous species, Atlantic salmon (AS) were cultured in media supplemented with NaCl to produce osmotic pressures
varying from 300 to 500 mOsm kg−1. The growth rates of the two cell lines were affected in a similar manner by the salinity of the media with the rank order
for both peak cell numbers and growth rates up to the day of peak cell number being 300 > 350 > 400 > 450 > 500 mOsm kg−1. Cell death occurred in both cell lines in older cultures at all salinities with the greatest loss of viable cells in media
of 300 and 350 kg−1. However, there were quantitative and qualitative differences between the cell lines in their lipid metabolism in response
to the salinity of the media. The lipid content expressed per cell showed a positive correlation between lipid per cell and
salinity in TF cells, but this was less apparent in AS cells. The percentage of total polar lipid classes increased with increasing
salinity in TF cells due mainly to graded increases in the percentages of choline phospholipids. In contrast, there were no
significant differences in the proportions of polar and neutral lipid classes with salinity in AS cells. The only significant
effect of salinity in AS cells was a decreased proportion of dimethylacetals in total lipid at the highest salinity. The same
significant effect of salinity on dimethylacetal content of total lipid was observed in TF cells. However, in addition there
was a graded decrease in the percentage of 18:2n-9 in TF cell total lipid with increasing salinity. This was accompanied by
increased percentages of total n-3 and n-6 PUFA with higher proportions of both groups of PUFA at 450 and 500 compared with
300 mOsm kg−1. The results show that environmental salinity, in the absence of hormonal or other physiological stimuli, has direct effects
on the growth and lipid metabolism of fish cells and that these effects differ in cells from different fish species. 相似文献